Dr. David Kisailus, University of California Riverside – Mantis Shrimp

In today’s Academic Minute, Dr. David Kisailus of the University of California Riverside explains how understanding the structure of a powerful little shrimp could lead to materials that are both stronger and lighter.

David Kisailus is an assistant professor of chemical and environmental engineering at the University of California, Riverside. His research is focused on the structure-function relationships of biomineralized tissues and the creation of biologically inspired nanoscale materials for energy-based applications. He holds a Ph.D. from the University of California Santa Barbara.

Much of materials engineering is focused on creating strong, light-weight and tough materials. With that in mind, my lab is studying the bright orange fist-like club of the mantis shrimp, a 4-inch long crustacean that resembles an armored caterpillar. The mantis shrimp club accelerates underwater faster than a 22-caliber bullet. The strike is so powerful that we keep the mantis shrimp in a special aquarium so it doesn’t break the glass. Repeated blows by the club can destroy mollusk shells and crab exoskeletons. And the club can withstand 50,000 high-velocity strikes on prey during its lifespan.

We wanted to know how the club could withstand that many impacts. What we found is a highly complex structure comprised of three specialized regions that work together to create a material tougher than many engineered ceramics. The first region is located at the end of club that actually impacts the prey. It contains a high concentration of mineral similar to that found in human bone that supports the impact when the mantis shrimp strikes prey. Further inside, highly organized and rotated layers of organic fibers in mineral act as a shock absorber. The final layer is a wrapping of these same oriented organic fibers, which keep it intact during these high velocity impacts.

There are many potential materials that could be developed based on the structure of the club. Our lab is primarily focused on military body armor, which can add 30 pounds to a service member’s load. Our goal is to develop a material that is one-third the weight and thickness of existing body armor, but with enhanced properties. There are also potential applications in vehicle and aircraft frames. For example, if electric cars weigh less, they consume less power and people will be able to drive them further. With airplanes, less weight would reduce fuel costs and better impact resistance would improve reliability and cut repair bills.